[Q] blinking gray triangle in notification bar

question: there's a blinking gray triangle outline in my notification bar.. why??
occasionally it will disappear, but it comes back quickly.. it also disappears if I reboot, but comes back quickly again. it wasn't there until I messed up my phone and had to restore it (see list below)
it has been like this for weeks..

I have attached a screenshot - you can see the gray triangle in the notification bar. it blinks on and off.
also, in settings->about phone->network, "Network" says "Unknown". don't see anything else unusual.

I noticed sometimes my text messages will not send, also gps seems to be worse.. not sure if either of these are related.

tried searching, found some stuff saying it's about roaming (but I'm not roaming), also found some stuff that led me to believe I might need a new sim card (can't seem to find those posts anymore though)

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